Kentrophoros
Kentrophoros is a genus of ciliates in the class Karyorelictea. Ciliates in this genus lack a distinct oral apparatus and depend primarily on symbiotic bacteria for their nutrition.
Systematics
Kentrophoros is the sole genus in the family Kentrophoridae Jankowski 1980. The type species of the genus is K. fasciolatus Sauerbrey 1928, first described from the Bay of Kiel. Synonyms are Centrophorus Kahl 1931 and Centrophorella Kahl 1935. Fifteen species of Kentrophoros have been formally described, although several of these names may be synonyms for the same species.Description
The ciliates are long and ribbon-shaped, like other karyorelictean ciliates that live in the marine interstitial habitat. In some species, the cell body is folded or involuted into a tube or more elaborate shapes. The ventral side is ciliated, while the dorsal side is mostly unciliated except for a single "circle kinety" at the margin. The dorsal side is covered with a single layer of symbiotic bacteria. Kentrophoros lacks a distinct oral apparatus, although densely-spaced kinetids associated with fibers at the anterior part of the cell may be vestiges of the oral apparatus. The number and arrangement of nuclei within the cell are also variable between species. Some species have only one micronucleus and two macronuclei, but others can have multiple clusters of macro- and micronuclei, or so-called "composite nuclei" where each cluster of macro- and micronuclei is enclosed in another membrane.Kentrophoros live in coastal marine sediments, where they prefer the interface between oxic and anoxic layers.